Different Types of Energy

Chemical energy is a form of potential energy and it is possessed by things such as food, fuels and batteries. Chemical energy is one form of potential energy, along with mechanical energy, gravitational energy, nuclear energy and electrical energy. All of these forms of energy are stored within an object and are converted to forms of kinetic energy when a force or change is applied. During chemical reactions, molecules can be created or destroyed. If a product is created, the chemical energy is stored in the bonds that make up the molecules. If something is broken down, the chemical energy is released, usually as heat. If a reaction releases energy, it is called exothermic, and if it absorbs energy, it is called endothermic.

Mechanical energy is the sum of energy in a mechanical system. This energy includes both kinetic energy, the energy of motion, and potential energy, the stored energy of position. Mechanical energy exists as both kinetic and potential energy in a system. Kinetic energy, the energy of motion, exists whenever an object is in motion.

Gravitational potential energy is energy an object possesses because of its position in a gravitational field. The most common use of gravitational potential energy is for an object near the surface of the Earth where the gravitational acceleration can be assumed to be constant at about 9.8 m/s². Formula: PE = mgh

Elastic potential energy is Potential energy stored as a result of deformation of an elastic object, such as the stretching of a spring. It is equal to the work done to stretch the spring, which depends upon the spring constant k as well as the distance stretched. Formula: PE = 1/2(k/x2). x is distance.

Thermal energy is generated and measured by heat of any kind. It is caused by the increased activity or velocity of molecules in a substance, which in turn causes temperature to rise accordingly. The laws of thermodynamics explain that energy in the form of heat can be exchanged from one physical object to another.

Sound energy is the energy produced by sound vibrations as they travel through a specific medium. Sound vibrations cause waves of pressure which lead to some level of compression and rarefaction in the mediums through which the sound waves travel. Sound energy is, therefore, a form of mechanical energy; it is not contained in discrete particles and is not related to any chemical change, but is purely related to the pressure its vibrations cause.